Discrete element modelling of drying shrinkage and cracking of soils

Abstract

This paper is aimed at showing the efficiency of discrete element modelling for the prediction and understanding of drying shrinkage and associated cracking. The discrete element approach used is presented first. Cohesive forces between grains, as well as drying shrinkage deformation, are included in the formulation. A numerical model is then used to simulate drying shrinkage experiments conducted on a fine-grained soil. The numerical simulations agree well with the experimental measurements. When drying shrinkage is constrained at the boundaries, and when moisture gradients develop in the drying soil, the model is able to predict the time of the occurrence of cracking, as well as the crack pattern formed. Finite element simulations and the discrete element approach both predict similar behaviours before cracking occurs. The proposed discrete element approach is highly promising for studying the origins and causes of cracking in soils.